Marie-Belle de Winter is the daughter of Milady de Winter as well as a Rebel.
Marie seems to be cold, ruthless, and untrustworthy. But once someone really takes the time to get to know her, she can be really sweet. Marie is loyal, kind, and protective towards her loved ones. She is cunning and alluring by nature. Marie has learned to hide her emotions and tell good lies, as it's her destiny to become the French spy who betrays her own country. But surprisingly, Marie doesn't want to be a French spy. She wants to become an author and write stories. Marie almost always keeps her cool under pressure. She feels vulnerable at EAH because with all her training and studying, she has never had the chance to be a teenager, therefore, she doesn't know much about the normal teen life. It also doesn't help that she has no parents to guide her. She keeps her distance from the other students, thinking that letting them in would make her more vulnerable. She does, however, talk to the other students, usually in a sarcastic manner. Marie hates it when the Royals treat others like they're beneathe them. It also annoys her when the staff does it, too. Marie tends to be suspicious to the point where she's paranoid. She can be somewhat romantic, even though she hates to admit it. She believes in true love, and because of that, she refuses to use her ability of manipulating guys into falling for her. She is good-hearted, not wanting to hurt any of the soon-to-be musketeers who she is destined to harm.
Marie has long raven black hair. She has pale skin, a slender figure, indigo eyes, and long eyelases that frame her eyes. Her lips are full, her eyebrows are perfectly arched, and she has a straight nose.
Her mother is Milady de Winter, the well-known French spy. Marie's mother was beheaded and killed in the story. She doesn't know where her birth father is. So, she can be considered as an orphan. She deeply misses her mother, and is confused by how she could miss someone, while barely knowing her. She also hates her mother for what she did, and is also confused by herself missing someone she dislikes.
Marie doesn't have many friends.
Marie has a pet horse named Anne. Marie has learned how to shoot arrows while riding on it. Anne is an obedient horse, but she is always eager to be challenged when it comes to riding.
Marie-Belle is known to capture the hearts of many at EAH, but she doesn't want to date anyone yet. She has a voice that can bewitch any guy at EAH to fall for her, but she refuses to use it unless it is completely matter-of-life-or-death necessary.
- Her horse's name refers to the name "Anne de Breuil," which was the name Athos knew Milady de Winter by when they first met.
- Marie is skilled with the rapier, the musket, and the bow and arrow.
- She can imitate many accents, but she is best at the English accent.
- Marie dislikes her ability to attract men. She sees their affection toward her as fake, and that they probably only like her because of her appearance, or because of her mother's ability itself.
- Marie speaks with a French accent.